Flexible tray for carburizing furnaces



Jan. 31, 1939. F. J. BLANEY 2,145,708

FLEXIBLE TRAY FOR CARBURIZING FURNACES Filed April 6, 1938 JO 2? I 1 .2%

I m 21 Z1 46 J2 :15 & 4

4 .1412 25 20 v Q W? 24 m Zwezzor Patented Jan. 31, 1939 FLEXIBLE TRAYFOR CARBURJZIN FURNACES Fred J. Blaney, Springfield, Ohio, assignor toThe Ohio Steel Foundry Company, Lima, Ohio,

a corporation of Ohio Application April 6, 1938, Serial No. 200,340

4 Claims.

This invention relates to improvements in work trays for carburizingfurnaces and the like, on which material is supported for treatmentunder high heat conditions.

The principal object of the invention is to provide an improved form ofheat-resisting tray having flexibility as one of its principal charac--v teristics. Said tray is made of separate pieces, loosely joinedtogether, so as to overcome the effects of unequal stresses ordinarilyinducedby heat in rigid structures of the type previously employed forthe purpose, which stresses usually resulting in warping, twisting andbreakage of the tray, and shortening of its useful life. I

The invention may 'best be understood by reference to the accompanyingdrawing, in which Fig. 1 is a plan view of a tray constructed inaccordance therewith.

Fig. 2 is an end view of the tray illustrated in Fig. 1, showing itmounted on supporting rails.

Fig. 3 is an enlarged detail perspective view of one of the crosssupports with the supporting bars removed and a part of a tie rodpartially withdrawn from one end thereof.

Fig. 4 is a detail section taken on line 4-4 of Fig. 1. I

In the embodiment of my invention illustrated in the drawing, the trayis indicated generally at It], and is designed to'be supported insliding engagement along rails H, II which may pass as usual through acarburizing or other furnace of any suitable form, details of which neednot be shown herein. The tray is provided to support work or materialwhile it is being treated under high heat conditions in such furnaces.While especially adapted forprogression through a continuous furnaceas'suggested, the tray can also be used with other types of furnaces.

The tray is made up of a plurality of parallel 4O equispaced supportingbars l2, l2 held together at their opposite ends by the tie bars l4, l4

passing loosely through an end hole in each of said bars, and alsothrough hollow spacing tubes I6, I 6 which define the distance betweenadjacent 5 bars. The outer ends of said tie bars have heads M Hlsuitably fixed thereon, as by welding, and

loosely engaging the outer faces of the outermost bars.

Adjacent each end of the't'ray and extending 50 the full width thereofis a support or runner l8 including a web I!) in supporting relationbelow the supporting bars l2. and a plurality of hollow rectangularbosses 20, 20 formed integral with said web. Said bosses projectupwardly between 55 adjacent pairs of bars, but with the side faces ofeach pair of adjacent bosses spaced apart to form a channel to receivethe intermediate bar in loosely fitting engagement therein. The runnersl8 also have integral end pieces 2i, 2] loosely fitting against theouter face of the outermost 5 bars. In the form shown, the runners I8,88 are designed to be slidably rnountedmon the"tracklmie rails, andtherefore each of said runners is spaced apart to register with saidrails, and also has an integral depending flange 22 along one edge 10thereof to form guides for the tray.

The runners are connected to each of the supporting bars by tie bars 24,which as herein shown are relatively flat and extend in looseflttingengagement through registering holes or l5 slots 25, 25 in the bosses20, and similar holes-or slots 26, 26 in the bars l2. The tie bars M areloosely fastened in place, as for instance by welding one end of eachbar to one of the end pieces 2|, as indicated at 21, and providing theopposite 20 end with a head 28 in loose-fitting engagement in acountersunk recess 29 formed in the opposite end piece.

With the loose-fitting construction above described, the bars arepermitted to have limited 25 universal movement in any direction withrespect to the furnaces or supports.

One or more additional transverse supports may also be provided, asindicated at 30. In the form shown, the single support at the center 30of the tray is similar in construction and arrangement to the runnersi8, i8, excepting that it does not have a depending flange to engage atrack.

The operation and advantages of the tray above described will now beunderstood. The bars [2, i2 35 form a substantial supporting surface forthe work, but are flexibly supported and loosely connected together bythe end tie bars M, II and intermediate supports l8 and 30, allaffording a structure sufiiciently rigid for its intended purpose, andyet sufliciently flexible and loosely connected to accommodate itself tothe differences in expansion and contraction, and thus be able towithstand the varying temperatures and, resulting stresses and shocksimposed thereon, without warping or breaking. It is also capable ofcompensating for unevenness of the supporting rails, when progressedtherealong in a'continuous rurnace. The parts of the tray are simple andeconomical to manufacture. and broken parts can be readily replaced asrequired, rather than discarding the entire tray on account of failureof a single part thereof. I

Although I have shown and described one particular embodiment of myinvention. it will be I understood that I do not wish to be limited tothe exact construction shown and described, but that various changes andmodifications may be made without departing from the spirit and scope ofmy invention as defined in the appended claims.-

I claim as my invention:

1. In a work tray for'furnaces, a plurality oi? parallel supporting barsand a plurality of transversely disposed supporting members, each ofsaid supporting members including a plurality of spacing members, andconnecting-means passing through said spacing members and all of saidsupporting bars to provide loose fitting vertical and lateral engagementbetween said supporting bars and said supporting members at a pluralityof points both along the margins and between opposite margins of thetray, whereby the tray structure can readily accommodate itself tostresses due to temperature changes imposed on the several partsthereof.

a plurality of points both along the margins and between oppositemargins of the tray, and certain of said supporting members havingdepending guide means formed integral therewith for arearoe 3. In a worktray for furnaces, a plurality ofsimilar parallel supporting bars and aplurality of transversely disposed supports having loose connectiontherewith, at least some of which comprise continuous bottom webs eachhaving integral upstanding projections with channels therebetween'adapted to receive said bars in loose fitting engagement therein, saidbars and said projections having registering holes therethrough, and atiebar passing in loose fitting engagement through said holes wherebyeach of said bars has limited universal movement relative to each ofsaid supports.

4 In a work tray for furnaces, a plurality of similar parallelsupporting bars and a plurality of transversely disposed supports havingloose connection therewith, at least some of which comprise continuousbottom webs each having depending guide means adaptedfor engagement witha track rail, and integralupstanding projections with channelstherebetween adapted to receive said bars in loose fitting engagementtherein, said bars and said projections having registering holestherethrough,v and a tie bar passing in loose fitting engagement throughsaid holes whereby each of said bars has limited universal movementrelative to each of said supports.

FRED J. BLANEY.

